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Mery Daniel couldn't wait for Marathon Monday. It was one of the things the aspiring doctor and Haitian immigrant loved most about living in Boston.

"I was waiting patiently for that day," says Mery, sitting on a park bench in Boston's South End. "Last year I went (to the Boston marathon) and I had so much fun. So I wanted to go again this year."

Hundreds of people were crowded around the race's end point on April 15 around 2:50 p.m. when evil unfolded.

"I was at the finish line. The moment I got there, that was when I heard the blast," Mery says.

Authorities accuse brothers Tamerlan and Dzhokhar Tsarnaev of setting off a pair of bombs just seconds apart near the finish line of the packed course on Boylston Street. Three people were killed and more than 260, including Mery, were injured.

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"I didn't realize I was losing my leg because it happened so fast," Mery said, recounting the horrific events of that day.

Tamerlan Tsarnaev was killed four days later in a shootout with police, and his younger brother, Dzhokhar, was captured and charged with 30 federal counts stemming from the attack. He has pleaded not guilty to the charges.

After the bombs exploded, Mery was rushed to Massachusetts General Hospital with severe injuries to her lower limbs. She recalls asking doctors in the emergency room to save her leg, but they couldn't. Not only were doctors fighting to save Mery's left leg -- they were fighting to save her life. Her heart stopped twice during surgery. She was in a coma for three days. At just 31, she's been to hell and back.

When she woke up, Mery says, "I just looked up and my leg wasn't there anymore. I wasn't part of the decision process -- it just wasn't there anymore."

Her left leg was amputated above the knee. Her right leg was spared, but it was severely mangled from the explosion and she lost a significant portion of her right calf. "I didn't really go through that mind frame like, 'I'm losing my leg and how am I supposed to react or how am I supposed to respond to it'... So it did surprise me how much I handled it."

Mery said an inner strength emerged when she least expected it. "Sometimes, you don't know the limits of how far you can go until you're tested."

Two victims lost both of their legs in the bombings. Fourteen others lost one leg. Waking up to realize you've suddenly lost a limb can be devastating. While the body heals and adapts, doctors agree that the recovery of the mind can be a bigger challenge.

Recovery of mind and body

Recovery for Mery has been both physical and emotional. "There are moments you wish your leg was there," she says, while still acknowledging the new reality that she and her family have had to come to terms with. The challenges are there, even in the most simple tasks, but Mery is determined to learn to walk again and to live her life. "I want to continue on and do everything I was meant to do and move forward."

The loss of a large part of her right calf makes holding the weight of her body on her right leg alone even more difficult. But Mery takes each step with determination.

"I don't mind people staring. It is what it is. And that's the new me now and I have to be comfortable." She makes a point of saying how much she loves dresses and says she won't stop wearing them just because people stare at her injuries.

But the wounds frightened her five-year-old daughter, Ciarra. At first, the little girl was afraid of what remained of her mother's left leg.

Mery Daniel and her daughter, Ciarra, on June 26, 2013.

"She didn't want to come near it, she didn't want to touch it, she didn't want anything to do with it. She constantly was asking me, why did I have to go to the bomb?"

It's taken a few months, but on this day Ciarra runs into the apartment after school and gives her mother a big hug -- no longer afraid of her injuries. "I think it means a lot -- mommy's coming back to normal," Mery says.

"It's been very tragic to see someone you love go through that," says Mery's husband, Richardson Daniel. But he's been astounded by her strength. "I don't have any doubt that she will be great and I don't think that she will have a problem to attain the goal that she has in life."

Mery says the tragedy actually brought the couple closer.

"He is more understanding now and I think I'm more understanding, too." She laughs, noting the two fight less often now.

The bombs nearly took the life of someone who embodies the American dream. Mery came to the United States when she was 17 years old. She married Richardson Daniel, a fellow Haitian, and gave birth to their daughter. She then moved to Poland to attend medical school before returning to Boston.

Mery spent six weeks in the hospital after the attack, undergoing multiple surgeries. When she was finally released, there was another challenge: She couldn't go home. The stairs in her duplex proved too difficult to tackle. For now, she and her husband are living in a temporary, first-floor apartment. Adjusting to a new home hasn't been easy, but Mery says she finds comfort listening to music and cooking. When we were there, the scent of stir-fried chicken and vegetables filled the apartment.

A new leg, a new life

Mery Daniel takes her first steps on her new prosthetic leg on June 26, 2013.

It was a hot June day when we joined Mery at United Prosthetics. It was the day she had been waiting for -- the day she was getting her new leg.

"How are you feeling?" I ask Mery.

"Excited!" she replies, sitting in a chair as one of the employees she'd gotten to know from her multiple visits here removed the dressing from what remains of her left leg.

Prosthetist Paul Martino enters the room with Mery's new leg. Although she'd had several fittings, she's surprised at the size. "That's what I'm getting?" As she examines the leg, her initial excitement turns to concern.

Martino explains that a small battery will power her new knee, which is computerized and controlled by the amount of weight Mery puts on the leg. As Mery tries it on for the first time, she says it feels awkward and heavy. She's worried about falling when she tries to walk with her new leg. But she doesn't let her fear get in the way and uses her crutches to help her stand up.

With Martino's help, she begins to take steps.

But walking is tough, even with crutches. She has trouble bending the knee and says it hurts "where my knee used to be." She slowly walks up and down a narrow hallway as a computer in a nearby room measures her gait and works to calibrate her computerized knee.

After just a few minutes, Martino takes one crutch away from Mery, encouraging her to put more weight on her prosthetic leg. "I'm not comfortable yet," she says. But she doesn't fall or even hesitate as she takes slow, steady steps. And with each one, her excitement quietly returns. "It's hopeful. Like I'm going to be able to walk and do things I want to do."

The team at Boston's Spaulding Rehabilitation Hospital will now help Mery learn to do more and more.

"I describe myself as the last responder," quips Dr. David Crandell. He's the director of Spaulding's Amputee Program and is leading Mery's rehabilitation. As he displays how the parallel bars in the hospital will help Mery relearn how to walk, he points out that for amputees, their mental strength is just as important as physical strength in recovery.

"There's a lot of joy of taking those first several steps, but then also there's the realization that it's actually a lot of hard work and they're really going to need continued rehabilitation." In fact, rehabilitation often lasts a lifetime, as prosthetic technology changes and improves.

Dr. Crandell says his work with Mery will continue indefinitely. "As long as she stays in the Boston area, for the rest of my career, most likely."

Since the bombing, Mery says her insurance hasn't put up a fight about paying her medical bills. Her new leg alone cost $50,000. But Dr. Crandell worries that years down the road, as Mery and other amputees from the bombing try to get new prosthetics -- either for the advanced technology or for cosmetic purposes -- insurance may not cover those costs. "Sometimes they will cover a basic but they may not cover the full or the higher-end prosthesis, so the patient has to be a good advocate," he says. "We have to be able to show that the added cost has real value; value in function and in quality of life."

Fellow fighter

One person who has greatly helped improve Mery's quality of life as she heals is fellow amputee and paralympian Bonnie St. John, who paid her a surprise visit in the hospital after the bombing. "She's a hero to me," St. John says of Mery. "She's a real American hero." St. John helped Mery set up a fundraising website to help cover the cost of her mounting medical bills. She's also helped Mery see that losing her leg doesn't mean losing her life.

Mery is determined to become a doctor in family medicine and talks about studying for her boards. But now she also has another goal: to "motivate people" as St. John has done for her. "You never know how strong you are until you have no choice but to be," Mery says.

In moments of weakness, Mery says she looks down at her necklace, which was given to her by a fellow survivor.

"Never, never, never give up," it reads.

"I now look at things for what they are and see the positive in things," she says. "And when you get to do that, you get to see the beauty in life."